Method and apparatus for providing ue assistance information on rrc state preference in wireless communication system

Abstract

A Method and Apparatus for multi-SIM operation during handover is provided. The method includes receiving an RRC reconfiguration message from a base station including configuration of terminal assistance information related to an RRC state transition; initiating a terminal assistance information process based on said configuration information in said RRC control message; and initiating one of T1 and T2 based on UEAssistanceInformation, receiving an RRCReconfiguration message including a ReconfigWithSync for a target SpCell, sending an RRCReconfigurationComplete message from said target SpCell, initiating transmission of a UEAssistanceInformation after successful completion of a random access procedure at the target SpCell, and initiating T2 after initiating transmission of the UEAssistanceInformation if said UEAssistanceInformation includes a musim-PreferredRRC-State IE.

What is claimed is: 
     
         1 . A method by a terminal in a wireless communication system, the method comprising:
 receiving, by the terminal from a base station, a first Radio Resource Control Reconfiguration (RRCReconfiguration), wherein:
 the first RRCReconfiguration comprises a parameter related to state transition of the terminal; and 
 the parameter related to state transition of the terminal comprises a parameter indicating length of a first timer; 
   transmitting, by the terminal to the base station, User Equipment Assistance Information (UEAssistanceInformation), wherein the UEAssistanceInformation comprises a parameter indicating state of the terminal;   starting, by the terminal, the first timer after initiating transmission of the UEAssistance Information; and   restarting, by the terminal, the first timer after a second timer stops in case that the terminal:
 received a second RRCReconfiguration, wherein the second RRCReconfiguration comprises a parameter for synchronous reconfiguration (reconfiguration WithSync); 
 initiated transmission of the UEAssistanceInformation during a specific period; and 
 is configured to provide UEAssistanceInformation, 
   wherein:
 the second timer starts upon reception of the second RRCReconfiguration; and 
 length of the second timer is determined based on the reconfiguration WithSync. 
   
     
     
         2 . The method of  claim 1 ,
 wherein expiry of the first timer causes the terminal to perform:
 Medium Access Control (MAC) reset; 
 cell selection; and 
 state transition from CONNECTED state to IDLE state. 
   
     
     
         3 . The method of  claim 2 ,
 wherein expiry of the second timer causes the terminal to perform:
 MAC reset; 
 cell selection; and 
 transmission of Radio Resource Control Reestablishment Request (RRCReestablishmentRequest). 
   
     
     
         4 . The method of  claim 1 , the method further comprising:
 transmitting, by the terminal to the base station before receiving the first RRCReconfiguration, a RRC message comprising capability information on Multi-Universal Subscriber Identity Module (MUSIM) assistance data.   
     
     
         5 . The method of  claim 1 , the method further comprising:
 stopping, by the terminal, the first timer in case that a mobility from new radio command (MobilityFromNRCommand) is received;   releasing, by the terminal, Medium Access Control (MAC) configuration; and   releasing, by the terminal, at least one radio link control entity and at least one packet data convergence protocol control entity.   
     
     
         6 . The method of  claim 1 , the method further comprising:
 stopping, by the terminal, the first timer in case that a Radio Resource Control Release (RRCRelease) is received;   releasing, by the terminal, default Medium Access Control (MAC) configuration; and   reestablishing, by the terminal, at least one radio link control entity.   
     
     
         7 . A terminal in a wireless communication system, the terminal comprising:
 a transceiver configured to transmit and receive a signal; and   a controller configured to:   receive from a base station a first Radio Resource Control Reconfiguration (RRCReconfiguration), wherein:
 the first RRCReconfiguration comprises a parameter related to state transition of the terminal; and 
 the parameter related to state transition of the terminal comprises a parameter indicating length of a first timer, 
   transmit to the base station User Equipment Assistance Information (UEAssistanceInformation), wherein the UEAssistanceInformation comprises a parameter indicating state of the terminal,   start the first timer after initiating transmission of the UEAssistanceInformation, and   restart the first timer after a second timer stops in case that the terminal:
 received a second RRCReconfiguration, wherein the second RRCReconfiguration comprises a parameter for synchronous reconfiguration (reconfiguration WithSync); 
 initiated transmission of the UEAssistanceInformation during a specific period; and 
 is configured to provide UEAssistanceInformation, 
   wherein:
 the second timer starts upon reception of the second RRCReconfiguration; and 
 length of the second timer is determined based on the reconfiguration WithSync.